‘Grey’s Anatomy’ Milestone Episodes Ranked From Worst to Best

T.R. Knight as George O'Malley and Katherine Heigl as Izzie Stevens, Caterina Scorsone as Amelia Shepherd and Kelly McCreary as Maggie Pierce, and Ellen Pompeo as Meredith Grey in 'Grey's Anatomy'
Scott Garfield/ABC/Courtesy: Everett Collection, Anne Marie Fox/Disney, ABC

Grey’s Anatomy just aired its 450th episode, which means that if you were to binge the medical drama without breaks, it would take you about two whole uninterrupted weeks to watch every episode that has hit ABC so far.

And the show’s staying power even has the cast members blown away. “I think I had gotten to the show shortly before the 250th episode. And I was like, ‘Whoa, this show is going to be off the air pretty soon. 250 episodes? That’s a lot, so surely, this must be nearly the end,’” Kelly McCreary, who returned to Grey’s for the 450th episode, told TV Insider. “And then we did the 300th celebration, then the 350th, and then I was there for the 400th, too, actually, now that I think about it. All of them seemed impossible milestones to reach.”

So how did Grey’s mark each of those milestones? Find out in the ranking below, in which we sort every 50th episode from least to most impactful.

Ellen Pompeo as Meredith Grey in 'Grey's Anatomy'
ABC

Episode 150: “She’s Gone” (Season 8, Episode 2)

Episode 150 seems like the first milestone episode that the Grey’s writers forgot about. Instead of some sort of momentous storyline, we get Meredith (Ellen Pompeo) hiding Zola from a social worker in a desperate bid to keep her adoption on track. Not a great look. Richard (James Pickens Jr.) at least comes out looking better as he takes the fall for Mer in the Alzheimer’s trial debacle.

Ellen Pompeo as Meredith Grey in 'Grey's Anatomy'
ABC

Episode 400: “You Are the Blood” (Season 18, Episode 20)

Season 18 ends with a bloodless cliffhanger both literally — there’s a stakes-raising blood shortage at the hospital — and figuratively — it was a drag that the last shot was Mer calling out after Nick (Scott Speedman). On the plus side, Jackson (Jesse Williams) and April (Sarah Drew) come back to the hospital and give shippers confirmation the fan-fave couple is back together.

Sandra Oh as Cristina Yang, Sara Ramirez as Callie Torres, and Ellen Pompeo as Meredith Grey in 'Grey's Anatomy'
Danny Feld/ABC/Courtesy: Everett Collection

Episode 200: “Puttin’ On the Ritz” (Season 10, Episode 4)

The Grey’s docs get out of their scrubs and dress to the nines for a circus-themed fundraising gala for the hospital. And because this is a medical drama, there’s of course a medical emergency: Specifically, an acrobat falls on the party planner. We’re not sure the Grey’s ringmasters were on top form here, but at least Patrick Dempsey got to show off his juggling skills.

Justin Chambers as Alex Karev in 'Grey's Anatomy'
ABC

Episode 350: “My Shot” (Season 16, Episode 8)

A medical board considers revoking Mer’s license, and in Justin Chambers’ final onscreen appearance, Alex enlists some of her former patients to speak on her behalf. Some of the patients had more emotional resonance than others — props to the producers for looping in Katie Bryce (Skyler Shaye), Mer’s first patient — but their testimonies and this episode’s flashbacks had us longtime fans in our feels. If only Alex got a better send-off…

Caterina Scorsone as Amelia Shepherd and Kelly McCreary as Maggie Pierce in 'Grey's Anatomy'
Anne Marie Fox/Disney

Episode 450: “We Built This City” (Season 22, Episode 2)

The show’s latest milestone episode reunites Meredith and Amelia with their sister Maggie, with McCreary making a one-off return to the show. Meanwhile, the surgeons’ responses to a forklift accident at the hospital reveals changing power dynamics, and Millin (Adelaide Kane) leads the other second-year interns in a memorial to Beltran (Natalie Morales), their fallen mentor. This episode looks backward and forward in equal measure, providing a rewarding experience for fans old and new.

Ellen Pompeo as Meredith Grey in 'Grey's Anatomy'
ABC

Episode 250: “Guess Who’s Coming to Dinner” (Season 12, Episode 5)

A dinner party at Mer’s house turns awkward for the host when Callie’s (Sara Ramirez) new girlfriend turns out to be Penny (Samantha Sloyan), one of the docs whose negligence led to Derek’s death. (“Perfect Penny killed my husband,” Mer says.) But the highlight of the episode is the blowout conversation between Mer and Amelia, who have been on parallel grieving processes.

Kate Burton as Ellis Grey in 'Grey's Anatomy'
ABC

Episode 300: “Who Lives, Who Dies, Who Tells Your Story” (Season 14, Episode 7)

After a roller coaster accident, a trio of injured riders reminds Mer and Alex of George, Izzie, and Cristina. The resemblance was a stretch, but this episode is loaded with nostalgia, from the filmed-on-location Seattle ferry scene and the soundtrack full of covers of Season 1 needle-drops. And the shot of Ghost Ellis (Kate Burton) in the operating room gallery, applauding Mer’s Harper Avery Award win? So sweet.

Kate Burton as Ellis Grey and Ellen Pompeo as Meredith Grey in 'Grey's Anatomy'
Michael Desmond/ABC/Courtesy: Everett Collection

Episode 50: “Wishin’ and Hopin’” (Season 3, Episode 14)

One of the most-watched episodes of Grey’s happens to be one of the best, thanks to a devastating scene between a suddenly-lucid Ellis and Meredith and a stranger-than-fiction story about a patient with toxic blood. Plus, a post-elopement Callie realizes she’s now Callie O’Malley. With humor and heart, this episode shows off Grey’s Anatomy’s best features.

T.R. Knight as George O'Malley and Katherine Heigl as Izzie Stevens in 'Grey's Anatomy'
Scott Garfield/ABC/Courtesy: Everett Collection

Episode 100: “What a Difference a Day Makes” (Season 5, Episode 22)

Shonda Rhimes herself scripted Episode No. 100, which seemed like it’d be the MerDer wedding episode but instead turned even more romantic. Bailey (Chandra Wilson) inspires Meredith and Derek donate to her wedding day to Izzie (Katherine Heigl) and Alex, since Izzie has an inoperable brain tumor. And George (T.R. Knight), in one of his final scenes on the show, helps Izzie walk down the aisle.